It is being built by Blue Forest, who specialise in über-luxury, sustainable tree houses and eco-lodges.

And the interior of the bar, while inspired by Basil’s, has been given some quirky touches of its own by The Goring’s interior designer, Russell Sage.

They have shipped in tons of sand, three fishing boats and a palm-thatched roof - as well as cocktails created by Basil.

Pin-up Pippa: Kate Middleton's sister smiles as she makes her way home

Pippa and her parents would have been able to choose from concoctions such as the Mustique Mule, the Hurricane David and Basil’s Rum Punch.

Earlier in the week, Pippa showed she had lost none of her athletic prowess by taking part in a triathlon.

Despite soaring temperatures, Kate’s younger sister earned a well-deserved medal after completing a 5km race in the GE Blenheim Triathlon, which takes place every year at Blenheim Palace in Oxfordshire.

Guests: Judith Chalmers and a male companion leave the Goring event

Dressed for the beach: Christopher Biggins wears a Hawaiian shirt and shorts to the event

Pippa was joined by two male friends and opted to do the running part of the competition while the boys completed tough swimming and cycling sections.

Dressed in a pink and grey vest, matching shorts, a £270 pair of Bulgari sunglasses and with an ankle tag to time her, Pippa breezed through her race, completing it in a time of 25 minutes and 30 seconds.

‘People were excited to see her,’ said Alex Coulson, an organiser of the event which attracted 6,000 spectators.

She's a winner: With another athlete at close quarters, Pippa Middleton crosses the finishing line at the GE Blenheim Triathlon

‘The boys completed their courses in good time and joined Pippa to run across the finishing line together.’

Pippa is well-known as a keen sportswoman. At Marlborough and Edinburgh University, she played hockey and tennis and, like her sister, works out daily.